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  <meta content="This specification describes multi-column layouts in CSS, a style sheet language for the web. Using functionality described in the specification, content can be flowed into multiple columns with a gap and a rule between them.    This is a delta specification over CSS Multi-column Level 1.            Once the level 1 specification is final,            its content will be integrated into this specification,            which will then replace it.            Until then, CSS Multi-column Level 2 only contains additions and extensions to level 1" name="abstract">
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   <p data-fill-with="logo"><a class="logo" href="https://www.w3.org/"> <img alt="W3C" height="48" src="https://www.w3.org/StyleSheets/TR/2016/logos/W3C" width="72"> </a> </p>
   <h1 class="p-name no-ref" id="title">CSS Multi-column Layout Module Level 2</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft, <time class="dt-updated" datetime="1970-01-01">1 January 1970</time></span></h2>
   <details>
    <summary>Specification Metadata</summary>
    <div data-fill-with="spec-metadata">
     <dl>
      <dt>This version:
      <dd><a class="u-url" href="https://drafts.csswg.org/css-multicol-2/">https://drafts.csswg.org/css-multicol-2/</a>
      <dt class="editor">Editor:
      <dd class="editor p-author h-card vcard" data-editor-id="43241"><a class="p-name fn u-url url" href="http://florian.rivoal.net/">Florian Rivoal</a> (<span class="p-org org">On behalf of Bloomberg</span>)
      <dt>Suggest an Edit for this Spec:
      <dd><a href="https://github.com/w3c/csswg-drafts/blob/master/css-multicol-2/Overview.bs">GitHub Editor</a>
      <dt>Issue Tracking:
      <dd><a href="https://github.com/w3c/csswg-drafts/labels/css-multicol-2">GitHub Issues</a>
     </dl>
    </div>
   </details>
   <div data-fill-with="warning"></div>
   <p class="copyright" data-fill-with="copyright"><a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 1970 <a href="https://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="https://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="https://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="https://www.keio.ac.jp/">Keio</a>, <a href="https://ev.buaa.edu.cn/">Beihang</a>). W3C <a href="https://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="https://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document">permissive document license</a> rules apply. </p>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>This specification describes multi-column layouts in CSS, a style sheet language for the web. Using functionality described in the specification, content can be flowed into multiple columns with a gap and a rule between them.</p>
   <p>This is a delta specification over CSS Multi-column Level 1.

          Once the level 1 specification is final,
          its content will be integrated into this specification,
          which will then replace it.
          Until then, CSS Multi-column Level 2 only contains additions and extensions to level 1</p>
    <a href="https://www.w3.org/TR/CSS/">CSS</a> is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, etc. 
  </div>
  <h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
  <div data-fill-with="status">
   <p> This is a public copy of the editors’ draft.
	It is provided for discussion only and may change at any moment.
	Its publication here does not imply endorsement of its contents by W3C.
	Don’t cite this document other than as work in progress. </p>
   <p> <a href="https://github.com/w3c/csswg-drafts/issues">GitHub Issues</a> are preferred for discussion of this specification.
	When filing an issue, please put the text “css-multicol” in the title,
	preferably like this:
	“[css-multicol] <i data-lt>…summary of comment…</i>”.
	All issues and comments are <a href="https://lists.w3.org/Archives/Public/public-css-archive/">archived</a>,
	and there is also a <a href="https://lists.w3.org/Archives/Public/www-style/">historical archive</a>. </p>
   <p> This document was produced by the <a href="https://www.w3.org/Style/CSS/">CSS Working Group</a>. </p>
   <p> This document was produced by a group operating under
	the <a href="https://www.w3.org/Consortium/Patent-Policy/">W3C Patent Policy</a>.
	W3C maintains a <a href="https://www.w3.org/2004/01/pp-impl/32061/status" rel="disclosure">public list of any patent disclosures</a> made in connection with the deliverables of the group;
	that page also includes instructions for disclosing a patent.
	An individual who has actual knowledge of a patent which the individual believes contains <a href="https://www.w3.org/Consortium/Patent-Policy/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="https://www.w3.org/Consortium/Patent-Policy/#sec-Disclosure">section 6 of the W3C Patent Policy</a>. </p>
   <p> This document is governed by the <a href="https://www.w3.org/2019/Process-20190301/" id="w3c_process_revision">1 March 2019 W3C Process Document</a>. </p>
   <p></p>
  </div>
  <div data-fill-with="at-risk"></div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li><a href="#introduction"><span class="secno">1</span> <span class="content"> Introduction</span></a>
    <li><a href="#interaction"><span class="secno">2</span> <span class="content">Module Interactions</span></a>
    <li><a href="#the-multi-column-model"><span class="secno">3</span> <span class="content"> The multi-column model</span></a>
    <li>
     <a href="#the-number-and-width-of-columns"><span class="secno">4</span> <span class="content"> The number and width of columns</span></a>
     <ol class="toc">
      <li><a href="#cw"><span class="secno">4.1</span> <span class="content"> <span class="property">column-width</span></span></a>
      <li><a href="#cc"><span class="secno">4.2</span> <span class="content"> <span class="property">column-count</span></span></a>
      <li><a href="#columns"><span class="secno">4.3</span> <span class="content"> <span class="property">columns</span></span></a>
      <li><a href="#pseudo-algorithm"><span class="secno">4.4</span> <span class="content"> Pseudo-algorithm</span></a>
      <li><a href="#stacking-context"><span class="secno">4.5</span> <span class="content"> Stacking context</span></a>
     </ol>
    <li>
     <a href="#column-gaps-and-rules"><span class="secno">5</span> <span class="content"> Column gaps and rules</span></a>
     <ol class="toc">
      <li><a href="#column-gap"><span class="secno">5.1</span> <span class="content"> <span class="property">column-gap</span></span></a>
      <li><a href="#crc"><span class="secno">5.2</span> <span class="content"> <span class="property">column-rule-color</span></span></a>
      <li><a href="#crs"><span class="secno">5.3</span> <span class="content"> <span class="property">column-rule-style</span></span></a>
      <li><a href="#crw"><span class="secno">5.4</span> <span class="content"> <span class="property">column-rule-width</span></span></a>
      <li><a href="#column-rule"><span class="secno">5.5</span> <span class="content"> <span class="property">column-rule</span></span></a>
     </ol>
    <li>
     <a href="#column-breaks"><span class="secno">6</span> <span class="content"> Column breaks</span></a>
     <ol class="toc">
      <li><a href="#break-before-break-after-break-inside"><span class="secno">6.1</span> <span class="content"> <span class="property">break-before</span>, <span class="property">break-after</span>, <span class="property">break-inside</span></span></a>
     </ol>
    <li>
     <a href="#spanning-columns"><span class="secno">7</span> <span class="content"> Spanning columns</span></a>
     <ol class="toc">
      <li><a href="#column-span"><span class="secno">7.1</span> <span class="content"> <span class="property">column-span</span></span></a>
     </ol>
    <li>
     <a href="#filling-columns"><span class="secno">8</span> <span class="content"> Filling columns</span></a>
     <ol class="toc">
      <li><a href="#cf"><span class="secno">8.1</span> <span class="content"> <span class="property">column-fill</span></span></a>
     </ol>
    <li>
     <a href="#overflow"><span class="secno">9</span> <span class="content"> Overflow</span></a>
     <ol class="toc">
      <li><a href="#overflow-inside-multicol-elements"><span class="secno">9.1</span> <span class="content"> Overflow inside multicol elements</span></a>
      <li><a href="#pagination-and-overflow-outside-multicol"><span class="secno">9.2</span> <span class="content"> Pagination and overflow outside multicol elements</span></a>
     </ol>
    <li><a href="#acknowledgments"><span class="secno"></span> <span class="content"> Acknowledgments</span></a>
    <li><a href="#priv-sec"><span class="secno"></span> <span class="content"> Privacy and Security Considerations</span></a>
    <li>
     <a href="#conformance"><span class="secno"></span> <span class="content"> Conformance</span></a>
     <ol class="toc">
      <li><a href="#document-conventions"><span class="secno"></span> <span class="content"> Document conventions</span></a>
      <li><a href="#conform-classes"><span class="secno"></span> <span class="content"> Conformance classes</span></a>
      <li>
       <a href="#conform-responsible"><span class="secno"></span> <span class="content"> Requirements for Responsible Implementation of CSS</span></a>
       <ol class="toc">
        <li><a href="#conform-partial"><span class="secno"></span> <span class="content"> Partial Implementations</span></a>
        <li><a href="#conform-future-proofing"><span class="secno"></span> <span class="content"> Implementations of Unstable and Proprietary Features</span></a>
        <li><a href="#conform-testing"><span class="secno"></span> <span class="content"> Implementations of CR-level Features</span></a>
       </ol>
     </ol>
    <li>
     <a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
     <ol class="toc">
      <li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
      <li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
     </ol>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
     </ol>
    <li><a href="#property-index"><span class="secno"></span> <span class="content">Property Index</span></a>
    <li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
   </ol>
  </nav>
  <main>
   <h2 class="heading settled" data-level="1" id="introduction"><span class="secno">1. </span><span class="content"> Introduction</span><a class="self-link" href="#introduction"></a></h2>
   <p class="issue" id="issue-e0a943d4"><a class="self-link" href="#issue-e0a943d4"></a> Add final content from previous level</p>
   <h2 class="heading settled" data-level="2" id="interaction"><span class="secno">2. </span><span class="content">Module Interactions</span><a class="self-link" href="#interaction"></a></h2>
   <p>This document defines new features not present in earlier specifications.
In addition, once final, it will replace and supersede the following:</p>
   <ul>
    <li>The <a href="https://www.w3.org/TR/css3-multicol">CSS Multi-Column Layout Module Level 1</a> 
   </ul>
   <h2 class="heading settled" data-level="3" id="the-multi-column-model"><span class="secno">3. </span><span class="content"> The multi-column model</span><a class="self-link" href="#the-multi-column-model"></a></h2>
   <p class="issue" id="issue-e0a943d4①"><a class="self-link" href="#issue-e0a943d4①"></a> Add final content from previous level</p>
   <h2 class="heading settled" data-level="4" id="the-number-and-width-of-columns"><span class="secno">4. </span><span class="content"> The number and width of columns</span><a class="self-link" href="#the-number-and-width-of-columns"></a></h2>
   <p class="issue" id="issue-e0a943d4②"><a class="self-link" href="#issue-e0a943d4②"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="4.1" id="cw"><span class="secno">4.1. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width" id="ref-for-propdef-column-width">column-width</a></span><a class="self-link" href="#cw"></a></h3>
   <p class="issue" id="issue-e0a943d4③"><a class="self-link" href="#issue-e0a943d4③"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="4.2" id="cc"><span class="secno">4.2. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-count" id="ref-for-propdef-column-count">column-count</a></span><a class="self-link" href="#cc"></a></h3>
   <p class="issue" id="issue-e0a943d4④"><a class="self-link" href="#issue-e0a943d4④"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="4.3" id="columns"><span class="secno">4.3. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-columns" id="ref-for-propdef-columns">columns</a></span><a class="self-link" href="#columns"></a></h3>
   <p class="issue" id="issue-e0a943d4⑤"><a class="self-link" href="#issue-e0a943d4⑤"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="4.4" id="pseudo-algorithm"><span class="secno">4.4. </span><span class="content"> Pseudo-algorithm</span><a class="self-link" href="#pseudo-algorithm"></a></h3>
   <p class="issue" id="issue-e0a943d4⑥"><a class="self-link" href="#issue-e0a943d4⑥"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="4.5" id="stacking-context"><span class="secno">4.5. </span><span class="content"> Stacking context</span><a class="self-link" href="#stacking-context"></a></h3>
   <p class="issue" id="issue-e0a943d4⑦"><a class="self-link" href="#issue-e0a943d4⑦"></a> Add final content from previous level</p>
   <h2 class="heading settled" data-level="5" id="column-gaps-and-rules"><span class="secno">5. </span><span class="content"> Column gaps and rules</span><a class="self-link" href="#column-gaps-and-rules"></a></h2>
   <p class="issue" id="issue-e0a943d4⑧"><a class="self-link" href="#issue-e0a943d4⑧"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="5.1" id="column-gap"><span class="secno">5.1. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-gap" id="ref-for-propdef-column-gap">column-gap</a></span><a class="self-link" href="#column-gap"></a></h3>
   <p class="issue" id="issue-e0a943d4⑨"><a class="self-link" href="#issue-e0a943d4⑨"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="5.2" id="crc"><span class="secno">5.2. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-color" id="ref-for-propdef-column-rule-color">column-rule-color</a></span><a class="self-link" href="#crc"></a></h3>
   <p class="issue" id="issue-e0a943d4①⓪"><a class="self-link" href="#issue-e0a943d4①⓪"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="5.3" id="crs"><span class="secno">5.3. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-style" id="ref-for-propdef-column-rule-style">column-rule-style</a></span><a class="self-link" href="#crs"></a></h3>
   <p class="issue" id="issue-e0a943d4①①"><a class="self-link" href="#issue-e0a943d4①①"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="5.4" id="crw"><span class="secno">5.4. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-width" id="ref-for-propdef-column-rule-width">column-rule-width</a></span><a class="self-link" href="#crw"></a></h3>
   <p class="issue" id="issue-e0a943d4①②"><a class="self-link" href="#issue-e0a943d4①②"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="5.5" id="column-rule"><span class="secno">5.5. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule" id="ref-for-propdef-column-rule">column-rule</a></span><a class="self-link" href="#column-rule"></a></h3>
   <p class="issue" id="issue-e0a943d4①③"><a class="self-link" href="#issue-e0a943d4①③"></a> Add final content from previous level</p>
   <h2 class="heading settled" data-level="6" id="column-breaks"><span class="secno">6. </span><span class="content"> Column breaks</span><a class="self-link" href="#column-breaks"></a></h2>
   <p>The previous level of this specification defined how
	the user agent must determine where column breaks are placed
	when content is laid out in multiple columns.
	The <a data-link-type="biblio" href="#biblio-css3-break">[CSS3-BREAK]</a> module has since been introduced
	to define how to break the content across pages,
	columns, or <a data-link-type="dfn" href="https://drafts.csswg.org/css-regions-1/#css-region" id="ref-for-css-region">CSS Regions</a>,
	and supersedes <a href="https://drafts.csswg.org/css-multicol/#column-breaks">the column break</a> section of <a data-link-type="biblio" href="#biblio-css3-multicol">[CSS3-MULTICOL]</a>.</p>
   <p>This specification defers to <a data-link-type="biblio" href="#biblio-css3-break">[CSS3-BREAK]</a> on this topic.</p>
   <h3 class="heading settled" data-level="6.1" id="break-before-break-after-break-inside"><span class="secno">6.1. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-before" id="ref-for-propdef-break-before">break-before</a>, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-after" id="ref-for-propdef-break-after">break-after</a>, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-inside" id="ref-for-propdef-break-inside">break-inside</a></span><a class="self-link" href="#break-before-break-after-break-inside"></a></h3>
   <p>The <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-before" id="ref-for-propdef-break-before①">break-before</a>, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-after" id="ref-for-propdef-break-after①">break-after</a> and <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-inside" id="ref-for-propdef-break-inside①">break-inside</a> properties are now defined in <a data-link-type="biblio" href="#biblio-css3-break">[CSS3-BREAK]</a>.</p>
   <h2 class="heading settled" data-level="7" id="spanning-columns"><span class="secno">7. </span><span class="content"> Spanning columns</span><a class="self-link" href="#spanning-columns"></a></h2>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span">column-span</a> property makes it possible for an element to span across several columns.
	This specification adds <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value" id="ref-for-integer-value">&lt;integer></a> to the values available in the previous level.</p>
   <h3 class="heading settled" data-level="7.1" id="column-span"><span class="secno">7.1. </span><span class="content"> <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span①">column-span</a></span><a class="self-link" href="#column-span"></a></h3>
   <table class="def propdef" data-link-for-hint="column-span">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-span">column-span</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">none <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one">|</a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value" id="ref-for-integer-value①">&lt;integer></a> <span id="ref-for-comb-one①">|</span> all <span id="ref-for-comb-one②">|</span> auto 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>none 
     <tr>
      <th>Applies to:
      <td>in-flow block-level elements 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified value 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete 
   </table>
   <p>This property describes how many columns an element spans across. Values are:</p>
   <dl>
    <dt><dfn class="css" data-dfn-for="column-span" data-dfn-type="value" data-export id="valdef-column-span-none">none<a class="self-link" href="#valdef-column-span-none"></a></dfn> 
    <dt><dfn class="css" data-dfn-for="column-span" data-dfn-type="value" data-export id="valdef-column-span-all">all<a class="self-link" href="#valdef-column-span-all"></a></dfn> 
    <dd>
     <p class="issue" id="issue-e0a943d4①④"><a class="self-link" href="#issue-e0a943d4①④"></a> Add final content from previous level</p>
    <dt><dfn class="css" data-dfn-for="column-span" data-dfn-type="value" data-export id="valdef-column-span-integer"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value" id="ref-for-integer-value②">&lt;integer></a><a class="self-link" href="#valdef-column-span-integer"></a></dfn> 
    <dd>
      The element spans the specified number of columns.
			Values must be greater than 0.
			If the specified integer value is equal to,
			or larger than the number of columns in the multicol element,
			the number of columns spanned will be the same as if <a class="css" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span②">column-span: all</a> had been specified. 
     <div class="issue" id="issue-bcb56b36">
      <a class="self-link" href="#issue-bcb56b36"></a>This definition is insufficent. 
      <ul>
       <li>Does <a class="css" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span③">column-span: 1</a> count as <span class="css" id="ref-for-propdef-column-span④">column-span: none</span>,
				or does it create a spanner (which is a BFC)? 
       <li>Which columns does it span? 
       <li>How does that affect height calculations, and interract with column-fill 
      </ul>
     </div>
    <dt><dfn class="css" data-dfn-for="column-span" data-dfn-type="value" data-export id="valdef-column-span-auto">auto<a class="self-link" href="#valdef-column-span-auto"></a></dfn> 
    <dd>
      The number of columns spanned by the element
			depends on its <a data-link-type="dfn" href="https://drafts.csswg.org/css-sizing-3/#min-content" id="ref-for-min-content">min-content</a> <a data-link-type="dfn" href="https://drafts.csswg.org/css-sizing-3/#outer-size" id="ref-for-outer-size">outer size</a> in the inline direction of the <a data-link-type="dfn" href="https://drafts.csswg.org/css-multicol-1/#multi-column-container" id="ref-for-multi-column-container">multi-column container</a>.
			If it is smaller than the used value of <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width" id="ref-for-propdef-column-width①">column-width</a>,
			this is the same as if <a class="css" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span⑤">column-span: none</a> had been specified.
			Otherwise, the number of columns spanned is the smallest positive integer <var>n</var> for which <code><var>n</var> × <var><a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width" id="ref-for-propdef-column-width②">column-width</a></var> + (<var>n</var> - 1) × <var><a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-gap" id="ref-for-propdef-column-gap①">column-gap</a></var></code> is larger than the <span id="ref-for-min-content①">min-content</span> <span id="ref-for-outer-size①">outer size</span>.
			If this would be larger than the number of columns,
			the number of columns spanned will be the same as if <span class="css" id="ref-for-propdef-column-span⑥">column-span: all</span> had been specified. 
     <p class="issue" id="issue-272b18ac"><a class="self-link" href="#issue-272b18ac"></a> If <a class="css" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span⑦">column-span: 1</a> does not do the same as <span class="css" id="ref-for-propdef-column-span⑧">column-span: none</span>,
			should this behave as <span class="css" id="ref-for-propdef-column-span⑨">column-span: 1</span> or as <span class="css" id="ref-for-propdef-column-span①⓪">column-span: none</span> when the element is small enough?</p>
   </dl>
   <p class="issue" id="issue-d62281db"><a class="self-link" href="#issue-d62281db"></a> Add final content from previous level
	possibly with adjustements to account for <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value" id="ref-for-integer-value③">&lt;integer></a> values</p>
   <h2 class="heading settled" data-level="8" id="filling-columns"><span class="secno">8. </span><span class="content"> Filling columns</span><a class="self-link" href="#filling-columns"></a></h2>
   <p class="issue" id="issue-e0a943d4①⑤"><a class="self-link" href="#issue-e0a943d4①⑤"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="8.1" id="cf"><span class="secno">8.1. </span><span class="content"> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-fill" id="ref-for-propdef-column-fill">column-fill</a></span><a class="self-link" href="#cf"></a></h3>
   <p class="issue" id="issue-e0a943d4①⑥"><a class="self-link" href="#issue-e0a943d4①⑥"></a> Add final content from previous level</p>
   <h2 class="heading settled" data-level="9" id="overflow"><span class="secno">9. </span><span class="content"> Overflow</span><a class="self-link" href="#overflow"></a></h2>
   <h3 class="heading settled" data-level="9.1" id="overflow-inside-multicol-elements"><span class="secno">9.1. </span><span class="content"> Overflow inside multicol elements</span><a class="self-link" href="#overflow-inside-multicol-elements"></a></h3>
   <p class="issue" id="issue-e0a943d4①⑦"><a class="self-link" href="#issue-e0a943d4①⑦"></a> Add final content from previous level</p>
   <h3 class="heading settled" data-level="9.2" id="pagination-and-overflow-outside-multicol"><span class="secno">9.2. </span><span class="content"> Pagination and overflow outside multicol elements</span><a class="self-link" href="#pagination-and-overflow-outside-multicol"></a></h3>
   <p class="issue" id="issue-e0a943d4①⑧"><a class="self-link" href="#issue-e0a943d4①⑧"></a> Add final content from previous level</p>
   <h2 class="no-num heading settled" id="acknowledgments"><span class="content"> Acknowledgments</span><a class="self-link" href="#acknowledgments"></a></h2>
   <p>This document builds upon Håkon Wium Lie’s work in <a data-link-type="biblio" href="#biblio-css3-multicol">[CSS3-MULTICOL]</a>,
	and is based on several older proposals and comments on older proposals.
	Contributors include:</p>
   <p class="issue" id="issue-45b97b73"><a class="self-link" href="#issue-45b97b73"></a> Add final level 1 contributor list</p>
   <h2 class="no-num heading settled" id="priv-sec"><span class="content"> Privacy and Security Considerations</span><a class="self-link" href="#priv-sec"></a></h2>
   <p>Delta spec lol</p>
  </main>
  <h2 class="no-ref no-num heading settled" id="conformance"><span class="content"> Conformance</span><a class="self-link" href="#conformance"></a></h2>
  <h3 class="heading settled" id="document-conventions"><span class="content"> Document conventions</span><a class="self-link" href="#document-conventions"></a></h3>
  <p>Conformance requirements are expressed with a combination of
	descriptive assertions and RFC 2119 terminology. The key words “MUST”,
	“MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”,
	“RECOMMENDED”, “MAY”, and “OPTIONAL” in the normative parts of this
	document are to be interpreted as described in RFC 2119.
	However, for readability, these words do not appear in all uppercase
	letters in this specification. </p>
  <p>All of the text of this specification is normative except sections
	explicitly marked as non-normative, examples, and notes. <a data-link-type="biblio" href="#biblio-rfc2119">[RFC2119]</a> </p>
  <p>Examples in this specification are introduced with the words “for example”
	or are set apart from the normative text with <code>class="example"</code>,
	like this: </p>
  <div class="example" id="example-ae2b6bc0">
   <a class="self-link" href="#example-ae2b6bc0"></a> 
   <p>This is an example of an informative example. </p>
  </div>
  <p>Informative notes begin with the word “Note” and are set apart from the
	normative text with <code>class="note"</code>, like this: </p>
  <p class="note" role="note">Note, this is an informative note. </p>
  <p>Advisements are normative sections styled to evoke special attention and are
	set apart from other normative text with <code>&lt;strong class="advisement"></code>, like
	this: <strong class="advisement"> UAs MUST provide an accessible alternative. </strong> </p>
  <h3 class="heading settled" id="conform-classes"><span class="content"> Conformance classes</span><a class="self-link" href="#conform-classes"></a></h3>
  <p>Conformance to this specification
	is defined for three conformance classes: </p>
  <dl>
   <dt>style sheet 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#style-sheet">CSS
			style sheet</a>. 
   <dt>renderer 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that interprets the semantics of a style sheet and renders
			documents that use them. 
   <dt>authoring tool 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that writes a style sheet. 
  </dl>
  <p>A style sheet is conformant to this specification
	if all of its statements that use syntax defined in this module are valid
	according to the generic CSS grammar and the individual grammars of each
	feature defined in this module. </p>
  <p>A renderer is conformant to this specification
	if, in addition to interpreting the style sheet as defined by the
	appropriate specifications, it supports all the features defined
	by this specification by parsing them correctly
	and rendering the document accordingly. However, the inability of a
	UA to correctly render a document due to limitations of the device
	does not make the UA non-conformant. (For example, a UA is not
	required to render color on a monochrome monitor.) </p>
  <p>An authoring tool is conformant to this specification
	if it writes style sheets that are syntactically correct according to the
	generic CSS grammar and the individual grammars of each feature in
	this module, and meet all other conformance requirements of style sheets
	as described in this module. </p>
  <h3 class="heading settled" id="conform-responsible"><span class="content"> Requirements for Responsible Implementation of CSS</span><a class="self-link" href="#conform-responsible"></a></h3>
  <p>The following sections define several conformance requirements
		for implementing CSS responsibly,
		in a way that promotes interoperability in the present and future. </p>
  <h4 class="heading settled" id="conform-partial"><span class="content"> Partial Implementations</span><a class="self-link" href="#conform-partial"></a></h4>
  <p>So that authors can exploit the forward-compatible parsing rules to assign fallback values, <strong>CSS renderers <em>must</em> treat as invalid
		(and <a href="http://www.w3.org/TR/CSS2/conform.html#ignore">ignore as appropriate</a>)
		any at-rules, properties, property values, keywords, and other syntactic constructs
		for which they have no usable level of support</strong>.
		In particular, user agents <em>must not</em> selectively ignore
		unsupported property values and honor supported values in a single multi-value property declaration:
		if any value is considered invalid (as unsupported values must be),
		CSS requires that the entire declaration be ignored. </p>
  <h4 class="heading settled" id="conform-future-proofing"><span class="content"> Implementations of Unstable and Proprietary Features</span><a class="self-link" href="#conform-future-proofing"></a></h4>
  <p>To avoid clashes with future stable CSS features,
		the CSSWG recommends <a href="http://www.w3.org/TR/CSS/#future-proofing">following best practices</a> for the implementation of <a href="http://www.w3.org/TR/CSS/#unstable">unstable</a> features and <a href="http://www.w3.org/TR/CSS/#proprietary-extension">proprietary extensions</a> to CSS. </p>
  <h4 class="heading settled" id="conform-testing"><span class="content"> Implementations of CR-level Features</span><a class="self-link" href="#conform-testing"></a></h4>
  <p>Once a specification reaches the Candidate Recommendation stage,
		implementers should release an <a data-link-type="dfn" href="http://www.w3.org/TR/CSS/#vendor-prefix">unprefixed</a> implementation
		of any CR-level feature they can demonstrate
		to be correctly implemented according to spec,
		and should avoid exposing a prefixed variant of that feature. </p>
  <p>To establish and maintain the interoperability of CSS across
		implementations, the CSS Working Group requests that non-experimental
		CSS renderers submit an implementation report (and, if necessary, the
		testcases used for that implementation report) to the W3C before
		releasing an unprefixed implementation of any CSS features. Testcases
		submitted to W3C are subject to review and correction by the CSS
		Working Group. </p>
  <p>
   Further information on submitting testcases and implementation reports
		can be found from on the CSS Working Group’s website at <a href="http://www.w3.org/Style/CSS/Test/">http://www.w3.org/Style/CSS/Test/</a>.
		Questions should be directed to the <a href="http://lists.w3.org/Archives/Public/public-css-testsuite">public-css-testsuite@w3.org</a> mailing list. 
<script src="https://www.w3.org/scripts/TR/2016/fixup.js"></script>
  </p>
  <h2 class="no-num no-ref heading settled" id="index"><span class="content">Index</span><a class="self-link" href="#index"></a></h2>
  <h3 class="no-num no-ref heading settled" id="index-defined-here"><span class="content">Terms defined by this specification</span><a class="self-link" href="#index-defined-here"></a></h3>
  <ul class="index">
   <li><a href="#valdef-column-span-all">all</a><span>, in §7.1</span>
   <li><a href="#valdef-column-span-auto">auto</a><span>, in §7.1</span>
   <li><a href="#propdef-column-span">column-span</a><span>, in §7.1</span>
   <li><a href="#valdef-column-span-integer">&lt;integer></a><span>, in §7.1</span>
   <li><a href="#valdef-column-span-none">none</a><span>, in §7.1</span>
  </ul>
  <aside class="dfn-panel" data-for="term-for-css-region">
   <a href="https://drafts.csswg.org/css-regions-1/#css-region">https://drafts.csswg.org/css-regions-1/#css-region</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-css-region">6. 
Column breaks</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-min-content">
   <a href="https://drafts.csswg.org/css-sizing-3/#min-content">https://drafts.csswg.org/css-sizing-3/#min-content</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-content">7.1. 
column-span</a> <a href="#ref-for-min-content①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-outer-size">
   <a href="https://drafts.csswg.org/css-sizing-3/#outer-size">https://drafts.csswg.org/css-sizing-3/#outer-size</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-outer-size">7.1. 
column-span</a> <a href="#ref-for-outer-size①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-integer-value">
   <a href="https://drafts.csswg.org/css-values-3/#integer-value">https://drafts.csswg.org/css-values-3/#integer-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-integer-value">7. 
Spanning columns</a>
    <li><a href="#ref-for-integer-value①">7.1. 
column-span</a> <a href="#ref-for-integer-value②">(2)</a> <a href="#ref-for-integer-value③">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-comb-one">
   <a href="https://drafts.csswg.org/css-values-4/#comb-one">https://drafts.csswg.org/css-values-4/#comb-one</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-comb-one">7.1. 
column-span</a> <a href="#ref-for-comb-one①">(2)</a> <a href="#ref-for-comb-one②">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-break-after">
   <a href="https://drafts.csswg.org/css-break-3/#propdef-break-after">https://drafts.csswg.org/css-break-3/#propdef-break-after</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-break-after">6.1. 
break-before, break-after, break-inside</a> <a href="#ref-for-propdef-break-after①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-break-before">
   <a href="https://drafts.csswg.org/css-break-3/#propdef-break-before">https://drafts.csswg.org/css-break-3/#propdef-break-before</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-break-before">6.1. 
break-before, break-after, break-inside</a> <a href="#ref-for-propdef-break-before①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-break-inside">
   <a href="https://drafts.csswg.org/css-break-3/#propdef-break-inside">https://drafts.csswg.org/css-break-3/#propdef-break-inside</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-break-inside">6.1. 
break-before, break-after, break-inside</a> <a href="#ref-for-propdef-break-inside①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-count">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-count">https://drafts.csswg.org/css-multicol-1/#propdef-column-count</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-count">4.2. 
column-count</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-fill">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-fill">https://drafts.csswg.org/css-multicol-1/#propdef-column-fill</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-fill">8.1. 
column-fill</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-gap">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-gap">https://drafts.csswg.org/css-multicol-1/#propdef-column-gap</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-gap">5.1. 
column-gap</a>
    <li><a href="#ref-for-propdef-column-gap①">7.1. 
column-span</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-rule">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule">https://drafts.csswg.org/css-multicol-1/#propdef-column-rule</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule">5.5. 
column-rule</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-rule-color">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-color">https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-color</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule-color">5.2. 
column-rule-color</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-rule-style">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-style">https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-style</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule-style">5.3. 
column-rule-style</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-rule-width">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-width">https://drafts.csswg.org/css-multicol-1/#propdef-column-rule-width</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule-width">5.4. 
column-rule-width</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-width">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width">https://drafts.csswg.org/css-multicol-1/#propdef-column-width</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-width">4.1. 
column-width</a>
    <li><a href="#ref-for-propdef-column-width①">7.1. 
column-span</a> <a href="#ref-for-propdef-column-width②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-columns">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-columns">https://drafts.csswg.org/css-multicol-1/#propdef-columns</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-columns">4.3. 
columns</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-multi-column-container">
   <a href="https://drafts.csswg.org/css-multicol-1/#multi-column-container">https://drafts.csswg.org/css-multicol-1/#multi-column-container</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-multi-column-container">7.1. 
column-span</a>
   </ul>
  </aside>
  <h3 class="no-num no-ref heading settled" id="index-defined-elsewhere"><span class="content">Terms defined by reference</span><a class="self-link" href="#index-defined-elsewhere"></a></h3>
  <ul class="index">
   <li>
    <a data-link-type="biblio">[css-regions-1]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-css-region" style="color:initial">css region</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-sizing-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-min-content" style="color:initial">min-content</span>
     <li><span class="dfn-paneled" id="term-for-outer-size" style="color:initial">outer size</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-values-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-integer-value" style="color:initial">&lt;integer></span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-values-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-comb-one" style="color:initial">|</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS3-BREAK]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-break-after" style="color:initial">break-after</span>
     <li><span class="dfn-paneled" id="term-for-propdef-break-before" style="color:initial">break-before</span>
     <li><span class="dfn-paneled" id="term-for-propdef-break-inside" style="color:initial">break-inside</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS3-MULTICOL]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-column-count" style="color:initial">column-count</span>
     <li><span class="dfn-paneled" id="term-for-propdef-column-fill" style="color:initial">column-fill</span>
     <li><span class="dfn-paneled" id="term-for-propdef-column-gap" style="color:initial">column-gap</span>
     <li><span class="dfn-paneled" id="term-for-propdef-column-rule" style="color:initial">column-rule</span>
     <li><span class="dfn-paneled" id="term-for-propdef-column-rule-color" style="color:initial">column-rule-color</span>
     <li><span class="dfn-paneled" id="term-for-propdef-column-rule-style" style="color:initial">column-rule-style</span>
     <li><span class="dfn-paneled" id="term-for-propdef-column-rule-width" style="color:initial">column-rule-width</span>
     <li><span class="dfn-paneled" id="term-for-propdef-column-width" style="color:initial">column-width</span>
     <li><span class="dfn-paneled" id="term-for-propdef-columns" style="color:initial">columns</span>
     <li><span class="dfn-paneled" id="term-for-multi-column-container" style="color:initial">multi-column container</span>
    </ul>
  </ul>
  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="normative"><span class="content">Normative References</span><a class="self-link" href="#normative"></a></h3>
  <dl>
   <dt id="biblio-css-regions-1">[CSS-REGIONS-1]
   <dd>Rossen Atanassov; Alan Stearns. <a href="https://www.w3.org/TR/css-regions-1/">CSS Regions Module Level 1</a>. 9 October 2014. WD. URL: <a href="https://www.w3.org/TR/css-regions-1/">https://www.w3.org/TR/css-regions-1/</a>
   <dt id="biblio-css-sizing-3">[CSS-SIZING-3]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-sizing-3/">CSS Intrinsic &amp; Extrinsic Sizing Module Level 3</a>. 22 May 2019. WD. URL: <a href="https://www.w3.org/TR/css-sizing-3/">https://www.w3.org/TR/css-sizing-3/</a>
   <dt id="biblio-css-values-3">[CSS-VALUES-3]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-3/">CSS Values and Units Module Level 3</a>. 31 January 2019. CR. URL: <a href="https://www.w3.org/TR/css-values-3/">https://www.w3.org/TR/css-values-3/</a>
   <dt id="biblio-css-values-4">[CSS-VALUES-4]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-4/">CSS Values and Units Module Level 4</a>. 31 January 2019. WD. URL: <a href="https://www.w3.org/TR/css-values-4/">https://www.w3.org/TR/css-values-4/</a>
   <dt id="biblio-css3-break">[CSS3-BREAK]
   <dd>Rossen Atanassov; Elika Etemad. <a href="https://www.w3.org/TR/css-break-3/">CSS Fragmentation Module Level 3</a>. 4 December 2018. CR. URL: <a href="https://www.w3.org/TR/css-break-3/">https://www.w3.org/TR/css-break-3/</a>
   <dt id="biblio-css3-multicol">[CSS3-MULTICOL]
   <dd>Florian Rivoal; Rachel Andrew. <a href="https://www.w3.org/TR/css-multicol-1/">CSS Multi-column Layout Module Level 1</a>. 28 May 2018. WD. URL: <a href="https://www.w3.org/TR/css-multicol-1/">https://www.w3.org/TR/css-multicol-1/</a>
   <dt id="biblio-rfc2119">[RFC2119]
   <dd>S. Bradner. <a href="https://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>. March 1997. Best Current Practice. URL: <a href="https://tools.ietf.org/html/rfc2119">https://tools.ietf.org/html/rfc2119</a>
  </dl>
  <h2 class="no-num no-ref heading settled" id="property-index"><span class="content">Property Index</span><a class="self-link" href="#property-index"></a></h2>
  <div class="big-element-wrapper">
   <table class="index">
    <thead>
     <tr>
      <th scope="col">Name
      <th scope="col">Value
      <th scope="col">Initial
      <th scope="col">Applies to
      <th scope="col">Inh.
      <th scope="col">%ages
      <th scope="col">Anim­ation type
      <th scope="col">Canonical order
      <th scope="col">Com­puted value
    <tbody>
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-span" id="ref-for-propdef-column-span①①">column-span</a>
      <td>none | &lt;integer> | all | auto
      <td>none
      <td>in-flow block-level elements
      <td>no
      <td>N/A
      <td>discrete
      <td>per grammar
      <td>specified value
   </table>
  </div>
  <h2 class="no-num no-ref heading settled" id="issues-index"><span class="content">Issues Index</span><a class="self-link" href="#issues-index"></a></h2>
  <div style="counter-reset:issue">
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4②"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4③"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4④"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4⑤"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4⑥"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4⑦"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4⑧"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4⑨"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①⓪"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①①"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①②"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①③"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①④"> ↵ </a></div>
   <div class="issue">
    This definition is insufficent. 
    <ul>
     <li>Does <a class="css" data-link-type="propdesc" href="#propdef-column-span">column-span: 1</a> count as <span class="css">column-span: none</span>,
				or does it create a spanner (which is a BFC)? 
     <li>Which columns does it span? 
     <li>How does that affect height calculations, and interract with column-fill 
    </ul>
     <a href="#issue-bcb56b36"> ↵ </a>
   </div>
   <div class="issue"> If <a class="css" data-link-type="propdesc" href="#propdef-column-span">column-span: 1</a> does not do the same as <span class="css">column-span: none</span>,
			should this behave as <span class="css">column-span: 1</span> or as <span class="css">column-span: none</span> when the element is small enough?<a href="#issue-272b18ac"> ↵ </a></div>
   <div class="issue"> Add final content from previous level
	possibly with adjustements to account for <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value">&lt;integer></a> values<a href="#issue-d62281db"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①⑤"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①⑥"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①⑦"> ↵ </a></div>
   <div class="issue"> Add final content from previous level<a href="#issue-e0a943d4①⑧"> ↵ </a></div>
   <div class="issue"> Add final level 1 contributor list<a href="#issue-45b97b73"> ↵ </a></div>
  </div>
  <aside class="dfn-panel" data-for="propdef-column-span">
   <b><a href="#propdef-column-span">#propdef-column-span</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-span">7. 
Spanning columns</a>
    <li><a href="#ref-for-propdef-column-span①">7.1. 
column-span</a> <a href="#ref-for-propdef-column-span②">(2)</a> <a href="#ref-for-propdef-column-span③">(3)</a> <a href="#ref-for-propdef-column-span④">(4)</a> <a href="#ref-for-propdef-column-span⑤">(5)</a> <a href="#ref-for-propdef-column-span⑥">(6)</a> <a href="#ref-for-propdef-column-span⑦">(7)</a> <a href="#ref-for-propdef-column-span⑧">(8)</a> <a href="#ref-for-propdef-column-span⑨">(9)</a> <a href="#ref-for-propdef-column-span①⓪">(10)</a>
   </ul>
  </aside>
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